# 定义中的参数 num1,num2称为形参

def sum_2_num(num1 , num2):
    """对两个数字求和"""
    # num1 = int(input("num1 = "))
    # num2 = int(input("num2 = "))
    result = num1 + num2
    print("%d + %d = %d" %(num1,num2,result))

# 调用函数中的num1，num2称为实参

sum_2_num(10,20)    